#include <bits/stdc++.h>
using namespace std;

int dx[13] = {0, -2, -1, -1, -1, 0, 0, 0, 0, 1, 1, 1, 2};
int dy[13] = {0, 0, -1, 0, 1, -2, -1, 1, 2, -1, 0, 1, 0};

int main()
{
    int n, m, k;
    cin >> n >> m >> k;
    int table[n + 5][n + 5] = {0}; // 总范围

    while (m--)
    {
        int x, y; // 火把
        cin >> x >> y;
        for (int i = 0; i < 13; i++)
        {
            // 处理越界问题
            table[x + dx[i]][y + dy[i]] = 1; // 1表示亮，0表示暗
        }
    }


    while (k--)
    {
        int o, p; // 萤石
        cin >> o >> p;
        table[o][p] = 1; // 先将自己点亮
        for (int i = o - 2; i <= o + 2; i++)
        {
            for (int j = p - 2; j <= p + 2; j++)
            {
                table[i][j] = 1;
            }
        }
    }

    int cnt2 = 0;
    for (int i = 1; i <= n; i++)
    {
        for (int j = 1; j <= n; j++)
        {
            if (table[i][j] == 0)
                cnt2++;
        }
    }
    cout << cnt2 << endl;

    return 0;
}